Starting mechanism for internal combustion engines



STARTING MECHANISM FOR INTERNAL-COMBUSTION ENGINES' Filed Dec. 6, 1945 Sept. 13, 1949. R. R. ROBINSON ET AL 3 Sheets-Shet l llllllll INVENTORS. RONALD R. ROBINSON JAY D- JOHNSON ATTORNEY.

Sept. 13, 1949. R. R. ROBINSON ET AL 2,481,783

STARTING MECHANISM FOR INTERNALCOMBUSTION ENGINES Filed Dec. 6, 1945 5 Shets-Sheet 2 Y i R W A //x //x l r N Y N I 3 m P eo I H 2 a a a f h v N Ob a;

g a w I Q h m a: N v n o n F m M a Q! o 0 g Q m m m N v v 0 5R 6 Q Q Q m m N! g 0 Q I INVENTORS. g In RONALD R. ROB/MSON "o JAY 0. JOHNSON c N BY M Q1 l. f I W I v ATTORNEY Se t. 13, 1949. R. R. ROBINSON ET AL 2,481,783

STARTING MECHANISM FOR INTERNAL-COMBUSTION ENGINES Filed D60. 6, 1945 3 Sheets-Sheet 5 EI E IN VENTORS. RONALD R- ROBINSON JAY D. JOHNSON' ATTORNEY Patented Sept. 13, 1949 UNITED STATES A PATENT oFF cs STARTING MECHANISM FOR INTERNAL- COMBUSTION ENGINES Ronald R. Robinson, Morton, and Jay D. Johnson, Peoria, 111., assignors to Caterpillar Tractor 00., San Leandro, Calif; a corporation of California Application December 6, 1945, Serial No. 633,120

8 Claims.

The present invention relates to starting mechanismfor internal combustion engines and par ticularlyto the construction of starting pinion.

latchingmechanisms and the?v arrangement of such mechanisms with relation to certain parts of a starting engine and the internal combustionengine which it is employed to start.

Patent No. 2,076,954 to Lewis for Engine whichissued on April 13, 1937, discloses a starting mechanism of'th'e' general type to which the present invention pertains. This patent discloses a primary engine having a smaller starting engine mounted alongside it and a driving connection including a pinion gear adapted to mesh with a ring gear on the flywheel of the primary engine. Latching mechanism is also disclosed for holding the pinion gear in mesh with the ringgear during startin'gof the primary engine and this latching mechanism extends beyond the pinion and ring gears and projects to the rear of the primary engine flywheel housing. This arrangement of starting mechanism has been found to have certain disadvantages. One

such disadvantage is that'the presence of the latching mechanism beyondthe flywheel housing interferes with the convenient positioning of other 1 auxiliary apparatus conventionally'located adjacent said housing. For example, in marine engines an electric generator is often so positioned and great inconvenience is caused by the presence of the latching mechanism in this position. ran-Q engine and a pinion gear driven thereby for engagement with a gear on the engine to be started and a latching mechanism forholding the pinion gear in mesh with the, gear on the engine with said latching mechanism located between-the starting engine andsaid gear. A still further object of the invention is the provision of a starting mechanism of the characterdescribed which includes a latching mechanism disposedv in a bath of lubricant. Further and." more specific objects and advantages of the invention are made apparent in the following deg;

tailed specification.

The invention is described and illustrated here- V in in its application to a primary engine of the a compression ignition type and a startng engine of the spark ignition type. It is to be understood, however, that this disclosure is merely illustrative of the principles of the invention which is readily adaptable to other types of primary engines and other types of starting engines or motors than those herein shown.

In the drawings:

Fig. 1 is a fragmentary view in side elevation of a primary engineand a starting engine therefor with parts broken away to show the normal relationship of the pinion and ring gears by means 7 of which starting motion is imparted to the pri-' mary engine;

Fig. 2 is an enlarged vertical central section through a portion of the clutch housing of the starting engme. the transmission housing thereof f. I

and a portion ofv the flywheel housing of the primary engine illustrating details oficonstruc tion'of the starting and latching mechanism;

Fig. 3 is a fragmentary section similar to Fig. 2 illustrating the position of certain parts when thelpinion gear is in mesh with the ring gear; Fig. 4 is a sectional View taken on line 4-4 of Fig. 3;

Fig. 5 is a sectional view taken on line 5-5 I of Fig.3;

Fig. 6 is a side elevation of a portion of the latching mechanism shown in Fig. 3 as viewed from the line 6- 6 of Fig. 5; and

Fig. '7 is a fragmentary plan view Fig. 2.

In Fig. 1 of the drawings a conventional internal combustion engine of the compression ignition type is shown at ID as provided with a fly-' wheel housing H and a conventional transmission case I2. On one side of. the block of the engine I0 is secured a starting engine l3 which is provided with a clutch housing [4 and a transmission case It: through which power is transmitted for rotating a pinion 16 which is adapted: to be broughtinto mesh with a ring gear I! on a flywheel N3 of the primary engine Id.

The manner in which power is transmitted. from the starting engine l3 to the pinion I6 is best illustrated in Fig. 2 wherein the clutch nous-1 ing i4 is shown as enclosing a flywheel 19 secured to' the end of a shaft 26 which is the crank shaft of the starting engine l3. The flywheel l9 has a recessed end which carries the driving plategl illustrating details of the transmission gearing shown in v the shaft 24 for rotation themwmlnpain fi driven plate 23 is mounted on ahubfieof t 3 of a clutch. The driven'plates of this clutch are shown at 22 and 23 and are mounted on a clutch v shaft 24. The clutch shaft 24 is supported at one end in a pilot bearing 25 received within a recessed end of the crank shaft 20 and at the 5 other end by ai-joeaiinjglZB received in; the 'c lutch housing Where it is held in place-by a snap ring J? 21 and a nut 28 threaded on the clutch shaft 24 as shown. An oil seal 28' is preferably disposed around the shaft 2% to prevent!the passage of; 1Q oil between the transmission case l5 and the clutch housing I. p H V The driven plate 22 of the clutch is' spline'd" driven plate 22 but held against relative rotation with relation to the plate 22 'byineaiis'fof a pin 30. A spider 3| is threaded to the hub 2 9, and carries toggle links 34: which are conneifti'd ener, fienventi e n lis e 2 11 s ml 2o whichis' slidably' mounted bat e erate li n mqvemeiit o ment or; release of, the clutchlin the" uter-r 1 to ew -diner QI MM hQPJ ttE Rl 39 pseem dfl eib insi e -bf ill s u s-h ii H 3 whigl 'gompels it and the clu'tc shaft to some 7+ n 131911113115 the flow. of oil ,hetwe e n the transmission case and the fiywheelhousing I I. D

129m mart-h z m mifi d EQP! t 9 h QflK-d onhthe clutch shaft ZQ meshes with qan ifi'l 'rotatable on a (counter "shaft 48" The nnie; sha t, i support d n. t ejt n inn Qn J A-Sin byen nfioml. ans sh wn- "Ih 1 gear 4]. isg-carried bywa hub gliwhich also be ries; sea mi dapteq tom sh, w ther. searhas a slidable driving connection with the ft L hi .d ,ebl driving connection includes a e 2; formed; integrally with the shaft fil; and its havin externally formed teeth,ingre fi yf it w teeth formed internally of r the gear' 5! ,tohprd! sleawhat is i 1* f t. s inedf n v B3? slidingthegear 5,! t0 the left asview 'g'. 2

l nternat eethrw la sohsreeis er. i ithiiie t ii; '70

oflgear gll, on the clutch sha ft zfi thus connect fi e ge ut h t e end ri ims iqn Sh t A i for; high" speed. .or direct transmission of pdwer frcgmgthc former to t l atte tu ,v i lm rementof' thegear 51' which establishe s' the hifi 75 forms atseal :against'fthwpassage' of'oilfrom the:

lts in sp position. The fork is slid ablealo t e shaft 55 by a manually operable lever? e "@156 Fig:- 13 which controls a shifting h hidli hasfihger' 59 embracing a part or the fbrktag v One end of he"traf'1smission shaft 4| extends intoithe fiywheel housing ll of the primary (ingine ai d is splined for sliding reception of the int r'iiallysplined pinion is. The transmission shaft is concentrically bored throughout its length ferthesudirig receipt-r6501 aflatch piii'fifl which haSa nut'Gl fixed to one endandwhich is con nect'e t its otheirfend,"'by 'f-an' inte'g'ral' flange" or bolla'rffiz; with thepinion 16 ?The*-co11ar%6'2 rests" a'gain'st'a" shouldeisin the-"boreiof vthe'pi ion "and' is held inv placef'therein tiby an "interna snap ring 63. Thei'splinediefidof 'thitransm sion"shaft"4l 'hasfan ""eiilarfig'dfhor forithe'sre ceptioriiof lfanf'exfiansime springffilavhich%sur;---- rounds'the'latch' pin 60 ndWhiCh "bQaiS ag'ains 1: the 'i'bl1aiii62 :at one end and-ragainst the inn r endfof the enlarged boreat the'other end'through th -medium of pakingland s5 rwhicli peie; mits' sliding movement- 'tof they-ia tch afiinffifl "but transmission fasei'to .the:flywh'1 housing. s ring :64. horma11yiiifges:the pinidfi "I 6, toward its gouterinosifpbsitioii' which limited "byit'henu 6 io'nirthe'; lfltch pir'r :Bfi aifidl Whicfh i'sjih; positio illustratedzin Fig. 2 wherein the pinion is not-in;

meshiwithther i gear. 11 t' i M.

'Whe thep e-sta n nemes s o l. t. io heo lm. Em lie-" hey n im r n e thel ni m e m ed tq m sh with the. iring gear b y sliding v l iji; h v

* eeh tseitbe i r s e etir i a gy guided T It is desired that the pinion gear remain in mesh'with the ring gear until the primary engine has been started and. brought up to sum-- cient speed under its. own power to assure its continued operation. In order to retain the pinion in mesh with the ring gear during'this period oftime, and against the pressure of the spring which tends to' return it to its normal position, a pair of pawls'15 arepivotally supported Within a diametrically disposed slot 16 in the transmission shaft H by pins 11, the-arrangement of which in' the shaft are best illustrated in Figs. 2 and '4. The pawls 15 are engageable with a peripheral groove 18 when the latch pin and pinion l6 are moved to the position illustrated in .Fig. 3. In thisposition the pawls l prevent the return of the pinion to its normal position under influenceof its, spring 64. The pawls 15 are constantly urged'toward their latching position by an expansible spring 19 which seats at one end against a-shoulder formed in the teeth of the gear 52. The other end of the spring 19 engages a nut 80 which is threaded on the exterior of a cage 8| which surrounds the shaft 4| and is interiorly grooved as at 82 to receive fingers 83 on the pawls 15. Through these connections, the spring 19 urges the pawls about their pivots TI toward the engaged position illustrated in Fig. 3. The pawls I5 are of sufficient size to act effectively as governor weights upon rotation of the shaft 4| by which they are carried. Consequently, when the primary engine has been started and attains a predetermined desired speed, it will impart speed to the pinion l6 and shaft 4| sufiicient to throw the pawls l5 outwardly about their pivots by centrifugal action, and against the tension of the spring 19, with the result that the latching engagement of the latch pin 6!] will be released and the pinion will return to the normal position of Fig. 2 under influence of spring 64. The tension of the spring 19 which regulates the speed necessary to disengage the pawls 15 may be adjusted by rotation of the nut 80 and a shouldered set screw 85 is carried by said nut as shown in Fig. 5 for engagement with any one of the plurality of notches 86 in the outer periphery of the cage 8|.

To enable assembly of the cage 8| over the projecting finger 83 of the pawls 15, the end of the cage is notched as indicated at 81 in Fig. 4 so that it may be slipped over the pawl fingers and then rotated ninety degrees so that the fingers will assume an effective position within the groove 82. The cage is held in its proper position by a set screw 88 (see Figs. 5 and 6) threaded into the shaft 4| and projecting into a slot 89 in the cage which prevents rotation of the cage on the shaft but permits its necessary endwise move ment.

With the construction described the entire latching mechanism which retains the pinion 16 in mesh with the ring gear on the flywheel of the primary engine is disposed within the transmission case which contains a bath of lubricating oil for lubrication of the transmission parts. Consequently, the latching mechanism is always adequately lubricated without the provision of special lubricating means. Furthermore, this arrangement positions the latching mechanism between the starting engine and the flywheel of the primary engine so that it does not project to an undesirable location as in previous structures.

The starting mechanism will operate in the manner herein described whether the transmission is adjusted for high speed or low speed and operation.

We claim: 1. Starting mechanism which comprises in combination a primary engine to be started and .a starting engine associated therewith, a first gear on the primary engine, a second gear adapted to be driven by the starting engine, a shaft supporting said second gear for axial movement into meshing engagement with the first gear, a

I grooved latch pin slideable in'said shaft and engaged with the second gear, and latch pawls pivotally carried by said shaft and engageable with the groove in said latch pin to retain the second gear in mesh with the first gear.

2. Starting mechanism which comprises in combination a primary engine to be started and astarting engine associated therewith, a first gear on the primary engine, a second gear adapted to be driven by the starting engine, a shaft supporting said second gear for axial movement into meshing engagement with the first gear, a grooved latch pin slideable in said shaft and engaged with the second gear, latch pawls pivotally carried by said shaft and engageable with said latch pin groove to retain the second gear in mesh with the first gear and resilient means normally urging the second gear away from its meshed position.

3. Starting mechanism which comprises in combination a primary engine to be started and a starting engine associated therewith, a first gear on the primary engine, a second gear adapted to be driven by the starting engine, a shaft supporting said second gear for axial movement into meshing engagement with the first gear, a grooved latch pin slideable in said shaft and engaged with the second gear, latch pawls pivotally carried by said shaft and engageable with said latch pin groove to retain the second gear in mesh with the first gear, said latch pawls being arranged for centrifugally impelled releasing movement upon rotation of the shaft, and resilient means for preventing such movement until the shaft attains a predetermined speed.

4. Starting mechanism which comprises in combination with a, primary engine to be started and a starting engine associated therewith, a gear on the primary engine, a pinion gear driven by the starting engine, means to move the pinion gear into and out of mesh with the gear on the primary engine, said means including a circumferentially grooved latch pin movable with said pinion gear and extending toward the starting engine and latch means interposed between the starting engine and the gear on the primary engine and engageable with said latch pin groove for holding said gears in mesh.

5. Starting mechanism which comprises in combination with a primary engine to be started and a starting engine associated therewith, a ring gear on the flywheel of the primary engine, a pinion gear driven by the starting engine, means for moving said pinion gear axially into mesh with the ring gear, said means including a circumferentially grooved latch pin carried by and movable with said pinion gear and extending toward the starting engine and latch means interposed between the starting engine and the ring gear and engageable with said latch pin groove for holding said gears in mesh.

6. Starting mechanism which comprises in .w Numberr. 1,210,028 J The followin'g fiefi'enslare qfdieord in the file pf this patent: v r 5 Dec. 26,, 1916 

